Really tough CR problem..Bio-engineered Cotton..

[suyash.tiwari]

Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year. This year the plantings are being seriously damaged by bollworms. Bollworms, however, are not necessarily developing resistance to the cotton’s insecticide. Bollworms breed on corn, and last year more corn than usual was planted throughout cotton-growing regions. So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

In evaluating the argument, which of the following would it be most useful to establish?
A. Whether corn could be bioengineered to produce the insecticide
B. Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year
C. Whether other crops that have been bioengineered to produce their own insecticide successfully resist the pests against which the insecticide was to protect them
D. Whether plantings of bioengineered cotton are frequently damaged by insect pests other than bollworms
E. Whether there are insecticides that can be used against bollworms that have developed resistance to the insecticide produced by the bioengineered cotton

The OA to this question is B.However, I am unable to get out of the following confusion:
In such question types:which of the following would it be most useful to establish?
If I am right, we look for choices that either strengthens or weakens the argument.(?)
From that point of view,B and D are both relevent.
If the Answer to D is yes, then the argument weakens.if the answer is No,the argument is strengthened.
How do you make D irrelevent ?

Thanks in Advance.

[davetzulin]

here's what i see with D

... This year the plantings are being seriously damaged by bollworms ...

D. Whether plantings of bioengineered cotton are frequently damaged by insect pests other than bollworms

D would then be meaningless, since we already have a premise saying the damage we care about is from bollworms.

for instance, doing the yes/no test on D
YES there are other insects damaging the plants fine, but bollworms are the ones "seriously damaging the plants".
there are NO other insects damaging the plants fine, but bollworms are still "seriously damaging" the cotton.

I noticed that this is just one of the tricks on CR questions. I think practically every problem I've done at least one answer choice is meaningless with respect to one of the premises, and given that there are always several premises, this gives a lot of options for wrong answers.

this problem was pretty hard and I only got to B using POE. Now after looking at it more carefully I think there is an unstated premise that B is attacking.

...Bollworms breed on corn, and last year more corn than usual was planted throughout cotton-growing regions....

...So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms....

the second is the conclusion of the stem and it requires an unstated premise, an assumption... "there are actually more bollworms" But the only thing you are guaranteed is that there is more corn and bollworms breed on corn, but it never guaranteed that there are more bollworms. the conclusion states that cotton was overwhelmed, implying a significant increase in bollworms.

B would basically destroy that assumption of more bollworms and attack the conclusion

[suyash.tiwari]

Hey, Thanks for your reply.
Yes, about D, I guess I missed the fact that it was going against a FACT, or a premise in your words, and we cannot NEGATE A FACT.

the second is the conclusion of the stem and it requires an unstated premise, an assumption... "there are actually more bollworms" But the only thing you are guaranteed is that there is more corn and bollworms breed on corn, but it never guaranteed that there are more bollworms. the conclusion states that cotton was overwhelmed, implying a significant increase in bollworms.

B would basically destroy that assumption of more bollworms and attack the conclusion

According to option B, it would be easy to deduce that non-bioengineered plants were planted every year along with bio-engineered plants. But this year, because of overwhelming production of bollworms due to large scale corn production, most of the nonbioengineered cotton is destroyed which was not the case in earlier years. Hence overall, the damage that happened to cotton crops was a lot.
I guess that defends B against your attack. :)

[RonPurewal]

If I am right, we look for choices that either strengthens or weakens the argument.(?)
From that point of view,B and D are both relevent.
If the Answer to D is yes, then the argument weakens.if the answer is No,the argument is strengthened.

nope. read the argument again, more carefully this time.

i presume you're thinking something like this: "if the plants suffered damage from some other pest, then it's less likely that the damage came from bollworms". in other words, you're casting this as, "i'm not sure whether the damage was caused by bollworms or by other little guys."

the problem is that the passage actually says, explicitly, that...
This year the plantings are being seriously damaged by bollworms

... thus putting that whole issue out of consideration.

[mtanutama]

Blue Book CR70

Strengthen
Conclusion: This year, serious damage to cotton is because of increasing # of corn-bred worms. Why?
Premise: Last year, more corns are planted and worms breed on corn.

Had D: Bioengineered cotton are also damaged by other pests, not only worms. This establishes that serious damage may not be due to corn-bred worms, but other pests that cotton does not have prevention mechanism against. Hmm...
Not D: Weakens. The argument also did not talk about other pests' effects on bioengineered cotton.
It's B: Cottons that do not have insecticide are suffering serious damage from worms. This establishes that cottons w no insecticide would be highly affected by increasing # of corn-bred worms and thus, account for the serious damage on cotton.
Not A: If corn could be bioengineered or not does not explain the serious damage to cotton.
Not C: Other crops. Stop. Argument talks about cotton. Evaluating other crops is not useful to establish the cause of damage to cotton unless the argument states relation of other crops to cotton.
Not E: Worms have developed resistance to the cotton's insecticide. This disagrees with the argument. Even if there are insecticides that can be used against the worms, it does not explain the serious damage incurred by cotton.

[tim]

Let us know if you have a question about this one.

[mtanutama]

Let us know if you have a question about this one.

Is it always true and right to think about stem Q1 and Q2 as strengthen questions, whose answers must always support the conclusion of the argument?

Stem Q1: Which answer would be most useful to establish to evaluate the argument (conclusion).
The conclusion must always be true and the answer to such stem Q has to always strengthen/support the conclusion of the argument, right?

(Reference to OG Blue Verbal Book CR66)
Stem Q2: Which answer would be most useful in evaluating the significance of the study described above, which is the conclusion?
My approach is to find an answer that strengthens and support the conclusion, but I have read an alternative that interprets this as a weakening question made me wonder if thinking of it as a strengthening question, like below is okay as well.

Strengthen
Conclusion: 217m acres of common grazing land is in BETTER condition than 433m acres of private grazing land.
Premise: Common grazing land is open to anyone and ALWAYS be used w less care.

Had A: Even if ranchers use both common and private, they'll tend to graze w less care at common than at private. But, this would result in common WORSE than private. Hmm...
Not B: =A.
Not E: If only common is used, and not private, common's got to be WORSE than private. Furthermore, there is no evaluation needed here, since there should not be a comparison between common and private in the first place.
Not D: Even if common users is as rich as private users, common should be in WORSE condition than private since ranchers tend to use common land w less care. So richer or not, here, has no impact.
It's C: If initial condition of common land is much better than private land, then this would explain to why common land could result in BETTER condition than private.

[RonPurewal]

Let us know if you have a question about this one.

Is it always true and right to think about stem Q1 and Q2 as strengthen questions, whose answers must always support the conclusion of the argument?

not really; you should think of them as "things that would strengthen or weaken the argument if we knew them".

for instance, here's a really simple example.
My friend, whose body weight has been the same for many years, has started eating more food than ever before. Therefore, she will gain weight.
--> example strengtheners:
* My friend is not exercising any more than she did before.
* My friend is eating more of the same foods she has always eaten.
* My friend just started taking a medicine that will slow down her metabolism.
--> example weakeners:
* My friend is exercising much more now than ever before.
* My friend is now eating foods with fewer calories per serving than those she previously ate.
* My friend just started taking a medicine that will speed her metabolism.
--> example things that will help evaluate the conclusion:
* How much my friend is exercising now, vs. previously, or, equivalently, Is my friend exercising more now than she did before?
* The relative calorie density of the foods my friend is now eating, compared to that of the foods she previously ate, or, equivalently, Has my friend started to eat foods that are more or less calorie-dense than the foods she previously ate?
* Whether my friend has started any medicines that will affect her metabolism, or, equivalently, Has my friend started taking any medicines that affect metabolism?

ok, i think you get the point: "evaluate the argument" generally has things that could go either way, depending on how they turn out.
the only real difference"”which honestly isn't a difference at all, in terms of the reasoning that's required"”is that strengtheners and weakeners are stated as facts, whereas "things that would help judge" are given as things we don't know yet.

[morn_ie]

I just did this question and chose wrong answer D!
my reasoning was that here we have a cause and effect relationship! so, to evaluate a cause and effect relationship we have to see whether other things can cause the effect or not! if yes, then the conclusion is wrong and if no, then we can say that the relationship is correct!
to me B is out of scope! because here we are not talking about non engineered cotton! in B it is assumed that if others suffer too much, for sure the bollworms can resist from the insecticide! we dont have any idea about those cottons.

if you reply a confused student, she will be grateful ;)

[RonPurewal]

I just did this question and chose wrong answer D!
my reasoning was that here we have a cause and effect relationship! so, to evaluate a cause and effect relationship we have to see whether other things can cause the effect or not! if yes, then the conclusion is wrong and if no, then we can say that the relationship is correct!
to me B is out of scope! because here we are not talking about non engineered cotton! in B it is assumed that if others suffer too much, for sure the bollworms can resist from the insecticide! we dont have any idea about those cottons.

if you reply a confused student, she will be grateful ;)

hi,
did you read the thread?

both of these choices are explained very nicely in earlier posts in this thread. it doesn't seem that you've read those yet -- particularly dave.tzulin's post about choice (d) -- so please go read those.
if you still encounter trouble with this problem, please quote the earlier replies and try to explain what you didn't understand about them (or else we'll have to give a reply that's essentially identical to what is already up there).

thanks.

[HARSHK668]

Can someone please tell me precisely how to break the paragraph into the structure such as premises, conclusion, background and counter premises so that i can have a greater insight of solving similar question.

[RonPurewal]

Those classifications are the topic of several chapters in the CR strategy guide.

It's not possible to give succinct "rules" for how to determine the role played by a given statement. (If we could actually do that, we'd be very, very rich"”we'd have solved one of the most perplexing conundrums in artificial intelligence.) Making those determinations is largely a matter of using your everyday human intuition.

[yaoL613]

hi experts:
i want to know why E is wrong.
cause if the answer is yes, then the increased damage on the plantings is due to the bollworms' resistances to the other kind of insecticides, but not the increases in corn plantation.

if the answer is no, then the increased damages on the plantings is due to the increases in corn plantation, but not the bollworms' resistances to the other kind of insecticides,

thx in advance!

[RonPurewal]

choice (e) asks merely whether those other kinds of insecticides exist. it certainly does not indicate that those other insecticides have actually been used on crops.

[yaoL613]

excellent！